1. Field of the Invention
The present invention is related to the field of HVAC systems for vehicles, especially school and commercial buses and the like and, more particularly, to an electronic climate control system with multi-function switches for such vehicles.
2. Description of the Related Art
High-occupancy passenger vehicles such as school buses and commercial buses have a dashboard area that includes a large number of switches and controls for adjusting the activation and operation of various heating, cooling, and lighting systems, among others. To accommodate these various switches, buses are typically manufactured to include a dashboard panel and/or adjacent control panel having a plurality of switch blanks or cutouts therein. These switch blanks are generally of the same approximate size such that they may be used interchangeably to mount various types of rocker-style switches. The rocker switches are also constructed to be of a standard, generally uniform size. By standardizing the switch blanks and the rocker switches, the location of specific switches within the overall control panel may be varied according to the needs of a particular bus or driver, since any of the most commonly used switches will fit into any of the common switch blanks.
Rocker switches of the type just summarized generally have only two positions, i.e., the switch is either turned on or off, as with a standard light switch. On a bus, these switches are suitable for controlling the on and off operation of various lights, fans, etc., as necessary. However, more complex systems such as the climate control system require a wider range of adjustments involving a greater number of parameters.
To provide the necessary range of control functions, conventional HVAC systems on buses have a set of controls presented to the driver through a faceplate that is considerably larger than the standard rocker switch blank. As a result, it is necessary to make a large customized cutout in the dashboard panel to accommodate the HVAC control unit. This complicates installation of the HVAC control unit as the location of the cutout must be properly determined and then the actual cutout made using the necessary tools. The skill of the installer is important as errors in placement and installation of the control unit faceplate can be costly and unsightly. In addition, the large panel that is cut out takes up a lot of space which, given the limited area available on the dashboard and adjacent panels, reduces the number of locations remaining for other controls and increases the visual complexity of the dashboard area for the driver.
Therefore, a need exists for an HVAC system having a control interface that takes up less space on the bus control panel while at the same time providing a wide range of control adjustment capability.